Ok i just bought a 1988 firebird formula, its got a 305 throttle body, i also own a 1990 camaro rs with the same motor. the Firbird has 90,000 miles on it, and the camaro has 118,000 i jsut replaced the waterpump and timing chain on the camaro, because i though the rattle noise that it was making was the chain slopping around. Well i was wrong, im going to replace the chain and pump on the formula anyway because i think it needs it. The noise that the car is making is an intermitant rattle, and i only really does it at an idle, the motor is not loud when i start it and both cars seem to be mechanically sound. What could this noise be? i have checked the ps pump, the air pump, the tensioner, the alternator, the ac pump, and the noise does not seem to be comming from any of those.